NCL30000

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Table 1. PIN FUNCTION DESCRIPTION

Pin

Name

Function

1

MFP

controller is disabled. In addition, this pin also has an over voltage comparator which will disable the controller in the

event of a fault.

2

COMP

The COMP pin is the output of the internal error amplifier. A compensation network is connected between this pin

and ground to set the loop bandwidth. Normally this bandwidth is set at a low frequency (typically 10 Hz − 20 Hz) to

achieve high power factor and low total harmonic distortion (THD).

3

external timing capacitor at the end of the on time cycle.

4

CS

The CS input is used to sense the instantaneous switch current in the external MOSFET. This signal is filtered by an

internal leading edge blanking circuit.

5

ZCD

The voltage of an auxiliary zero current detection winding is sensed at this pin. When the ZCD control block circuit

detects that the winding has been demagnetized, a control signal is sent to the gate drive block to turn on the

external MOSFET.

6

GND

This is the analog ground for the device. All bypassing components should be connected to the GND pin with a short

trace length.

7

DRV

The high current capability of the totem pole gate drive (+0.5/−0.8 A) makes it suitable to effectively drive high gate

charge power MOSFETs. The driver stage provides both passive and active pull down circuits that force the output to

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20 V.